Electrical connector



March 22, 1960 H. w. EARL 2,930,023

ELECTRICAL CONNECTOR Filed May 24, 1956 mum-II.)

F's-3 I FIGS.

INVENTOR. FIG. 4 HARRY W. EARL ATTORNEY du'ctors. 1

U ited S at 2,930,023 E T A EQT R Him w. Earl, South Marni, Fla. Application Main, 1956, Serial No. 537,085 I "3 or. 39-14 i invention relates, to electrical connectors andv is m re a ula y re ed to se a able n 'efl l l for electrical conductors for use with industrial equipment .ifei q t ns ea y e Ctt I utr nt II 7 This invention is an improvement, of the, connecto s cwn d des r bed. nmy, ope d l 'a p i t n Serial Num er 4,917.. fi ed feu i st. 18. 9 3. ent t ed E s trical Conector', issued on Febru ry' 5,,"1957, Patent'No, 2,780,792., e a

" A. pr pa bje t of the pre ent nv nt on. is to p o.- vide electrical connectorshavingfa male andfernal unit elesco ca l fi ng toge e Ifie t 'f r i n'al. t me w h P iv d' S 12 1 "d Y' W outflossto'the flow of electricity therethrough. z

A further object of the present invention is the provision of electrical connectors as described 'b'ove' which cannot be' inadve entlysepara'tedyet is re and just as readily disc "ectjed'by a SlIIl e, easy't'wis'tjin'g'"=ac' tion of onefpartj f the connectorf'relative to the mg A furtherobject of the present invention, is, to provide a separable electrical connector for the transmission of heavy currents which provide s' large contacting surfaces that are in tight contacting relatiomat all times thereby reducing current losses to a minimu'm.

A Still urt en biec qfz he present invention is the provision of separableelectr ical connectors characterized as above which are simple and inexpensive in construction and readily mounted on electricali cables for con- K With these and otherobjectsin view,"the invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawing forming a part of this specification, with the understanding, however, that the invention is not confined to any strict conformity with the showing of the drawing but may be changed or modified so long as such changes or modifications mark no material departure from the salient features of the invention as expressed in the appended claims.

In the drawing:

Figure 1 is a side elevational view of an electrical con-.

nector partially broken away, showing a male and female unit in their connected position.

Figure 2 is a longitudinal sectional view taken along the line 22 of Figure 1.

Figure 3 is an enlarged fragmentary view of the male and female units at their position of contact.

Figure 4 isa similar view to that shown by Figure 3 with the male and female units interlocked upon twisting or rotating one unit relative to the other.

Figure 5 is an enlarged fragmentary view showing the interlocking action between the male and female units.

Referring to the drawing wherein like numerals are used to designate similar parts throughout the several views, the numerals and 11 refer to a male and female unit respectively, which constitute the electrical connector embodying my invention.

connected c 2,930,023 sten d Me 1 6% ale unit 10 consists of a tubular member '12 con; d preferably of drawn copper though any electri: o'nduc'tingimetal may be used, having a further tubu ember telescopically mounted and secured therein." That, portionof the tubular member 13 which ex,- tends beyond thecnd of thetubular. member. 12 is slotted longitudinally as at 14, 14, The free end 15 of the tubular member -1 3 has its inner surface 16 tapered while the nearer. the tubular member 13 is of constant diame 1; throughout. A cable 17 with its insulation removed when distance of the end thereof extends within. the arimm er .13'opposite, tofthe end 15 and is secured the grip 20 'are countersunk therein sothat they do not comefifitocohtact with a person hadling the grip' 20.

female; unit 11 consists of a rubber grip 24 similar somc'v vhatlto the' gi'rip 2001 the male unit 10 mounted on atusularmmber 25 haying the samev diameter as tubular, memb 1: 12:61 the male unit'10. Thegrip 24 is likewise pres ed with an; annular recess 26 forming a lip 27fsimilarto'. the lip22Qof-thegrip 20. An expander or plug 28 positioned within the tubular member 25 is hollow orv tubular atone end. 29 receiving an uncovered pojr tion of an insulated cable 30 therein. Bolts 31 extend in mtoner si'zagrormea in the grip 24 are threaded through, the, sidewalls of the tubular member 215. and tubularf'po'rtionzQ of the plug 28 to form electrical cone tactfbetween the cable 30 with the tubular member12 5 an the plug 28, Theforward end 32 of the plug 28 is a' longitudinal slot 33. which extends] to. a

I ent tubular portion 29. The outer surface of the end 32 of the expander 23 is tapered as 'at 34 and a'ri anularrecess 35 is positionedinwardlyjof the tapered port' n3fl. Thetapered surface 3' 4increa ses in dii met rffrotfi' he re en of h j a l the ter beings'lightlysmaller' than the inside diameter of the tubular member 13 of the male plug 10. The tapered surface 34 increases in diameter to the rear thereof so that the largest diameter thereof is slightly larger than the inside diameter of the tubular member 13 but less than the largest diameter of the tapered surface 16 of the tubular member 13. 1

The expander 28 provides a double function; first, it yieldingly forces the extension 15 of the tubular member 13 of the male unit 10 into full contact relation with the tubular member 25 of the female unit 11 so that electricity will flow therethrough without loss or cause heating of the various parts thereoff; second, upon twisting the slots 14, 33 of the male and female units It! and 11 out of alignment as explained in detail hereinafter, the outward pressure exerted by the expander 28 at its largest diameter on the extension 15 along its tapered surface 16 causes the extreme end thereof to spring or distend inwardly as at 36 as shown by Figure 5, and thereby lock the two members together.

With construction as indicated above and cable 30 connected to a source of electricity, the male and female units 10 and 11, respectively are grasped by a person and aligned by positioning the bolts 18, 18 in alignment with the bolts 31. This places the slots 14, 14 of the male unit 10 in alignment with the slot 33 of the expander or plug 28. The extension 15 of the tubular member 13 is then fitted in the tubular member 25 of the female unit Its. 18, threadedthrough the side Walls of the H I e Lendof the tubular member 12. The bolts 18 ,"18, whichextend through bores 22 formed in 11 and permitted to be forced inwardly until the plug 28 is seated within the extension 15 as shown by Figure 3. In this position the extension 15 extends to the recess 35 and the expander 28 is forcibly urging .the tubular member *13 into contact relation with the tubular Inembe'r 25 and thereby providing a proper path for the flowrof' elec tricity therethrough. Also, as shown by Figure 3, the slots 14'of the tubular member "13 and the slot 33 which has become slightly compressed in alignment. The peripheral shape of the extension 32 of the plug 28 has changed from a circle to an oval due to the compression of the slot 33. Now, with the male and female units 10 and 11 in a persons grasp, the units 10 and 11 are each given a twisting force in the opposite directions causingthe slots 14 to move out of alignment with the slot 33. Upon the rotation of the slightly oval shaped plug 32 a tremendously increased force is exerted by virtue of a cam action ofthe plug 32 on the extension 15 efiecting a distention of the tubular extension 15 spreading diametrically opposite portions of the periphery of the extension 15 at the rear of the tapered portion of plug 28 more firmly against the inside of tubular member 25. It has been found that this twisting action while pushing the'units 10 and 11 together, causes the corresponding diametrically opposite portions of the outer edges of extension 15 tobend inwardly from the distended portions into the recess 35, as shown in dotted lines in Fig. at 36. The deformed tapered outwardly and a longitudinal slot on opposite walls extending along said outer end, a second tubular member having an inside diameter slidably fitting over the outside of said first tubular" member, and an expander member having a base portion fixed in the inner end of of said second tubular member and an enlarged extended portion with a diametrically slotted head positioned in spaced relation to the walls of said second tubular memher, said head having a tapered. surface matching the tapered inside surface at the outer end of said first tubular member for engagement therewith to form an extended surface contact when said tubular members are telescopically pushed together with said longitudinal slot edges of the extension 15 forms abutments or obstructions to prevent the plug 28 from being withdrawn from the tubular member 13 and the male and female units 10 and 11 from becoming inadvertently separated.

Now in order to break the separator by disconnecting the male unit 10 from the female unit 11, the male and female units are twisted until the bolts 18 and 31 are again in alignment thus bringing the slots 14 and 33 in alignment. With the plug 32 resuming its original position relative to that of the tubular member 13, the force exerted by the plug 28 is lessened and the extension '15 resumes its original shape, the distended portion 36 no longer extending itself inwardly in the direction of the recess 35. An outward pulling force is now exerted on each of the male and female units 10 and 11 until the plug 32 slides longitudinally out of the tubular member 13 to effect the complete separation of units 10 and 11. Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:l

' l. A separable electrical connector comprising a first tubular member having the inside surface of its outer end and said head slot in substantial alignment, said head being sharply undercut at its rear, the largest taper diameter at the rear edge of said tapered head being thus moved inwardly past the thin edges of the outer end of said first tubular member and the head compressed to a slightly oval shape, while the outer end of said first tubular member is stretched to conform to this shape and provide firm contact pressure between the outer surface areas of said first tubular member, diametrically opposite the sides of said head slot, and the corresponding inner surface areas of said second tubular member; whereby upon relative twisting movement of said tubular members, abutments are formed in the edge of the outer end of said first tubular member inwardly against the rear of said tapered head to substantially lock said members against inadvertent contact relaxation.

2. A separable electrical connector as defined in claim 1, and a tubular hand grip made of insulated material for each of said tube members for manual operation of said connector.

3. A separable electrical connector as defined in claim 2, each hand grip having a sleeve of conducting material extending inwardly from the inner end of the corresponding tubular member for the reception of a cable end, and counter-sunk clamp screws in said grip threaded through said sleeve against said cable end at a circumferential position in said grip indicating the diametrical position of the corresponding slot to facilitate the substantial alignment of said slots in the connecting operation.

References Cited in the file of this patent Earl Feb.v 5, 1957 

